Database

 

Design


microservice-per-database is the cleanest design for security and isolation:

  • Security: Each service only gets DB credentials for its own data. Even if compromised, it can’t access other services.

  • Resilience: Schema changes in one service won’t break another.

  • Scalability: You can shard or move a single microservice’s DB independently later.

  • Migration Flexibility: Easier to move a single service to another DB engine (MySQL → Postgres) if needed.

Who Creates the Database?

  • Database itself (schema): One-time setup (can be automated via migration tool like Alembic or manual Base.metadata.create_all()).

  • Each service: Creates only its own tables at startup if missing (idempotent).

Benefits of This Approach

  • Encapsulation: Each service owns its schema slice.

  • Loose coupling: No service can accidentally query/modify unrelated tables.

  • Easier migrations: Per-service migrations possible if schemas diverge.

  • Security: Can enforce MySQL users with limited table privileges.

Separate Models Per Service

  • api_gateway: Needs jobs table (for uploads & job status) and maybe users (if it grows beyond OIDC).

  • worker: Needs jobs table (to read queued jobs, mark complete/failed).

  • parser_service: Doesn’t need DB access (just parses and returns).

  • logging_service: Needs logs table (stores centralized logs).

  • identity (OIDC): Needs authcodes (stores short-lived codes for login).

Each service imports only its models — they don’t see each other’s tables.

Comments

Post a Comment

Popular posts from this blog

Feature: Audit log for one login, and identity service

Image
Customer (Product) Page High-Level System Design Diagram (PlantUML) Sequence Diagram: Audit Event Ingestion Sequence Diagram: Orchestration Event For a High-Level System (Component) Diagram The queue is implemented as message_queue (generic), and the audit log service consumes from it, writing to a dedicated audit_log table. The logging service also consumes from the same message_queue and writes to log_store. Orchestration/other services use the same queue. Summary Table: What Writes Where Event Type Goes Into Consumed By Final Storage audit message_queue Audit Log Service audit_log table log message_queue Logging Service log_store table doc_uploaded message_queue Orchestration Worker (business DB, or triggers next event) ocr_ready message_queue Notification Worker, etc. (notification log, etc.)  Core Tables message_queue – universal event bus (temp buffer) audit_log – immutable audit/compliance events log_store – application logs (op...
Read more

Getting started - Build your data science lab environment

This guide explains how to set up a complete data science environment for the udemy program. A proper setup ensures compatibility and avoids recurring environment issues.  1. Overview Goal : Create a full-featured environment with sufficient resources for all course exercises. Recommendation : Use Anaconda for the most reliable setup. Alternative : Use a Python virtual environment with pip if Anaconda isn’t working. 2. Setup Options Primary (Recommended) Create a dedicated Anaconda environment (isolated, compatible). Alternative Use a standard Python virtualenv + pip (faster but less reliable). 3. Windows Setup Steps Clone Course Repository git clone https://github.com/ed-donner/llm_engineering/ Follow the repository’s README.md instructions for additional setup details. Create Anaconda Environment Inside the llm_engineering folder: conda env create -f environment.yml ⏳ This may take several minutes. Activate the environment: conda activate llms Deactivat...
Read more

QA - Run #1 - Results

Image
# QA Report for Tag QA_July2025_A - **Tag/Commit:** QA_July2025_A (`f32abc1`) - **Date:** 2025-08-01 - **QA Outcomes:** All tests passed except for file upload (see below)... - **Environment:** Windows 10, Python 3.12, requirements.txt as of tag - **Notes:** See log for detailed results. ## Issue Found - **Step:** - **Bug:** - **Log excerpt:** - **Screenshot:** For this QA run, we begin with pristine state by: Stop all services Delete logs.db, and jobs.db Delete all files in doc_store folder Start all services Test, you should see no data on index page, and query should result in no data found error Next, go ahead and upload new1.txt, and after that new2.txt Issue the query: "can you summarize all of the todo items you can find, seperating each one on a single line, with due date first, then title, and description with any details you can augment" Expected Answer: - August 1, 2025: Respond to Amira and discuss weekend plans - August 3, 2025: Go to Somesh class and finish ta...
Read more